Automatic paper or foil break stop



April 1953 w. M. ROBINSON I 2,634,065

' AUTOMATIC PAPER 0R FOIL BREAK STOP Filed Dec. '18, 1947 Patented Apr. 7, 1 953 AUTOMATIC BAPER OR FOILsBREAK STOP William M. Robinson, Fairhaven, Mass.,*assignor to Cornell-Dubilier' Electric Corporation, South- Plainfield, N. J a corporation of Delaware 'ApplicationDecember 18, 1947,, Serial: No. 792,493

4"Ciaims.

1 I Q 7 I This invention relates toamachine jfor WlIldlH sheets of paper and metallized foil into a condenser .roll, each roll comprising metallic foils separatedflby numerous thins-tripsof dielectric paper. Anumber of thin strips. are used for separating the. foilsfthereby obtaining electric characteristics better. than. would be obtained by the use oisa single thick .insulatingstrip. By employing multiplesheets or strips, individual faults inanysheet, such asconducting particlespinholes and thalike are covered by other sheets, thus isolating the imperfections.

In practice the greater the number of insulating strips, thehigher is the voltage at which the condenser can beoperated.

.In. order .to-simplify terminology the various layers. forming the condenser roll will, here-after be referred to simply aspaper strips or sheets.

As the, thicknessesof the strips are decreased their mechanical strength is decreased, consequently in the manufacture of condensers employing very thin dielectric sheets by the cus tomary methods of manufacture, the tension applied to the sheets during the winding of the condenser will also have to be reduced. This leads to the production .of condensers having somewhat erratic capacity becauseof nonuniformity of the spacing between the sheets, due toinsu'fflcient tension. Furthermore, the-breaking of'the mechanically weak sheets leads torejections of imperfect condensers. .Itis impracti'calto visually check .the rolls of condenser strips during the Winding operation tomake sure that stripsifrom'all ofthe supply rolls arebeing wound into thecondenser.

. 'lfhe above trouble. is of lesser importance when using a hand winding machine, where an operator is on the job to remove finished windingsirom the machineandithus may be .able'to determine bythe actualsizeandfeel of the product whether any layers ofinsulating paper aremissing, but this is. not .true or automatic winding machines, one example or which is shown in Weiss Patent The present invention provides for automatically stopping the machine and/or indicate by visual or audible signal when any strip is broken during the winding operation. Repair of the break can then be made and the machine again set in motion.

'Theinvention also puts the entire control of the machine-and thestopping circuit under the control of, the operator, so that the operatorcan continue the winding, stop and make repairs-and then continue the winding independent of the stopping. mechanism or stopping circuit.

'In' the drawings:

Fig. 1 shows a device which makes the electrical contact to stop the machine when a break occurs;

Fig.3 is a. detailed view :of a portionof Fig. .2 which shows some of theparts in cross-section;

and

Fig. 4 is a schematic wiringdiagram of the invention.

Each of the many-strips I4 is led over asguide bar 15 (Fig. 1) and thence to mandrel 18 of; the winding machine (Fig.2). I ,A conventional .device, not'shown, maintains thestrips 'at-prope'r tension.

Mountedgon'each bar l5'is'a ball bearing collar l6. Projecting radially from collar 16 is a rod L having a portion bent degrees andpassing underneath strip [-4 and urged against the under surface thereof by a counterweight in the form of a bar K projecting frorn'the oppositeside of collar 16. Should a. strip M break (with consequent decrease in its tension) counterweight'K will fall or Ice-pulled down by a spring I1, raising. rod L'againstinsulated contact J, thus closing a control circuit and, giving a signal if desired.

Operation of winding mandrel l3-may be. understood. fromFigs'Z and'S. Pulley 2U, freely rotatable on shaft [9,, is driven continuously by a round belt B and maybe pressed, through resilientdisc 2 I ,into driving engagementwitha drum Dwhich iskeyed to the shaft bypin 41, thus rotating mandrel lflthrough gear v 22 and 23. A brake band E is .provided around drum D. The band E is operatedby solenoid 33, shown in Fig.- lain-the manner described below.

Pulley 2i! is urged into engagement withdi'um D .by means of a rotatable cap v25 on the endof an adjusting screw 2A threaded through the top of the vertical armofa hell crank 25' pivoted at 2*! .andhaving'cn the end of its horizontal arm a'friction or'hrake :pad 28 normally held against the rim :of drum Dbya spring 29. r

A chain 39 attached-to the'horiaontal armof bell crank z't leads to a foot pedal P. When a slight pull'is exerted on chain 30 brake pad 28is. moved out of engagement with the drum D, as" in Fig. 3. Simultaneously, 'thevertical arm of the bell crankZfi urges rotatable cap 25 against the projecting 'hub of pulley '20 thus putting just enough pressure on disc 2! to drum D, shaft l9, and mandrel S8 to rotate slowly and impositively under control of the operator through pedal P and chain T30 until he obtains proper tension on the various strips before the automatic contact circuit (Fig. 4) isinoperation with all contacts J and Lopen. Theme, further depression of pedal P will cause bell crank 26 to depress push, button 33,.thus closingswitch M toput the machinein its. normal running-condition under automatic control of a 6-volt circuit from the secondary transformer 34.

Referring to Figs. 1 and 4, it will be clear that with switch M closed and the machine in operation, if any strip l4 breaks, thereby permitting its bar L to bear against a contact J, relay 35 will be energized and contact plate 36 will break contact 40 to stop motor 39, and will engage contact 37, as shown in broken line in Fig. 4, to close the 110 volt circuit thus activating solenoid 38 and causing brake band E to grip drum D, thus instantly stopping rotation of mandrel l8.

In practice a motor switch 4| is provided, and a micro-switch 42 for a turn counter may be included in the circuit if desired.

What is claimed is: v

1. In a web handling apparatus wherein at least one web is wound upon a mandrel and wherein the web is to be maintained under a predetermined tension as it is wound on the mandrel operating at a predetermined speed, the combination for selectively controlling the mandrel speed until the desired tension is obtained and for automatically stopping the mandrel when there is a decrease in the predetermined tension of the web, comprising, a driving shaft, a web receiving mandrel rotated by said shaft, a driving means, clutch means disposed between the mandrel driving shaft and the driving means, operator-controlled means for impositively engaging the clutch for driving the mandrel at selective slow speeds below the predetermined speed, an automatic control switch for closing an automatic control circuit operated by the operator controlled means when the clutch means is fully engaged, the automatic control circuit including a motor circuit for operating the driving means and a braking circuit for stopping the driving shaft, a solenoid switch circuit for se lectively and alternately closing the motor and braking circuits and which when closed causes the motor circuit to be opened and the braking circuit to be closed, and switch means for closing the solenoid switch circuit which includes .a pair of contact devices one on each side of the web when the latter is under tension, one of the devices being stationary and the other movable, and a gravity device for maintaining the movable contact device in contact with the web, the gravity device being effective to move the movable contact device against the stationary contact device should the tension in the sheet be decreased.

2. In a machine for moving at least one web under predetermined tension, comprising, a mandrel for receiving the web under the predetermined tension, motor means for rotating the mandrel at a normal speed when the web is under the desired tension, automatic means which become operable when the mandrel is operated at said normal speed including means for stopping said motor means whenever the tension fails in said web, and means for applying a brake to said motor means, clutch means disposed between the mandrel and the motor means for connecting the mandrel and the motor means, operator-controlled means for impositively engaging the clutch means to drive the mandrel at selective speeds slower than the normal speed, and for positively engaging the clutch means to drive the mandrel at the said normal speed, switch means for closing the circuit of the automatic means actuated by the operator-controlled means when the latter is moved to positively engage the clutch means.

3.- In a motor driven machine for forming about a mandrel a roll from at least'one web under tension when the mandrel is driven at a predetermined speed, the combination, comprising, a mandrel, and mandrel-driving means, motor means, a clutch disposed between the motor means and the mandrel-driving means for positively driving the mandrel at the predetermined speed and for impositively and selectively driving the mandrel at speeds less than the predetermined speed, an automatic control means operable when the mandrel driving means is positively driven by the motor means, the automatic control means including a motor circuit for controlling the motor means and a braking circuit for stopping the mandrel driving means, a solenoid switch circuit for selectively and alternately closing the motor and braking circuits and which when closed causes the motor circuit to be opened and the braking circuit to be closed, tension failure switch means for closing the solenoid switch circuit which includes a pair of contact devices one on each side of the web when the latter is under tension, one of the contact devices being stationary and the other movable, means for maintaining the movable contact device in contact with the web and effective to move the movable contact device against the stationary contact device when the tension in the sheet is decreased.

4. In a motor driven machine for forming about a mandrel a roll from at least one web under tension when the mandrel is driven at a predetermined speed, the combination, comprising, a mandrel, and mandrel-driving means, motor means, a clutch disposed between the motor means and the mandrel-driving means for positively driving the mandrel at the predetermined speed and for impositively and selectively driving the mandrel at speeds less than the predetermined speed, an automatic control means operable when the mandrel driving means is positively driven by the motor means, the automatic control means including a motor circuit for controlling the motor means and a braking circuit for stopping the mandrel driving means, a solenoid switch circuit for selectively and alternately closing the motor and braking circuits and which when closed causes the motor circuit to be opened and the braking circuit to be closed, tension failure switch means for closing the solenoid switch circuit which includes a pair of contact devices, one of said contact devices being movable toward the other contact device and maintained out of contact with said other contact device by means engaging the web under tension, said movable contact device being adapted to engage the other contact device when there is a reduction in tension.

WILLIAM M. ROBINSON.

REFERENCES CITED The following references are of record in the file of, this patent:

UNITED STATES PATENTS Number Name Date 605,478 Gibbs et a1. June 14, 1898 1,149,013 Beregh Aug. 3, 1915 1,260,819 Schwarzmann et a1. Mar. 26, 1918 1,658,372 DeMoos Feb. 7, 1928 1,968,166 Phythian et al July 31, 1934 2,001,347 Holmes May 14, 1935 2,241,141 Knab May 6, 1941 

